Problem with seedlings PLSHELP *pics

Hello guys. Thank you in advance for all the help, suggestions and everything.
These babies are on their 5th day since germination in 45%coco40%soil and 15%perlite mix . Lights are cob led 25 cm away from the plants.
The temp is around 29-31celsius(because its hot outside and its hard to keep it cool) I have air outtake and 2 ventilators running. Humidity is between 40-50%. I have NOT given any nutrition yet to the seedlings. The seedlings look a bit pale green(not deep green) and the tips started to burn.
So I have 2 questions.
Why are they pale and not deep green?
And why are the tips "burning"?
Any suggestions? This happened only on a few plants. Not all, but all are raised in the same environment.
Water ph is aprox. 6,7-6,8 and I'm letting the "coco-soil-perlite mix kinda dry out and then I water them. I watered them 2 times with aprox. 200ml 6,8ph water in the last 5 days. The cups are medium dry and not light yet, can feel there is still water in the cup.

Sorry for the bad pics, if necessary I can take better ones
Appreciate all the help. Thank you
P.s. made a similar post, but got no response so I made another one. sorry

Kinda looks like light burn on the tips I'm new to indoor lighting so I could be wrong. Seedlings don't need very much light tho

My first advice is to not mix substrates. Choose either coir or peat/soil based with added perlite. You mix rockwool, coir and peat. This only causes water stagnation and possible rot at the stem core where you want great aeration.

Water requirements are way different with peat and coir, your out of luck for good advices because you've already started at the wrong end tbh.

look fine to me, start to worry when you see the cotyledons yellowing. bottom pic has some signs of root rot setting in